Develop Reference

Building a multidimensional object of form values using loops

I have this form that calculates the value of the radio button checkbox and quantity. I want to loop the name and value of every checked or selected item into a multidimensional object array. I am using the storeArray function to do this but all i could do was this tab = {Apple: 1, Orange: 2, quantity: 7}
But I want to be able to do something like so..
tab = {name: Apple, value: 1,}{name:Orange, value: 2}{name: quantity, value: 7}. I tried my best, I guess I'm not doing it right.
function storeArray() {
var tab = {};
$('*[data-in="num"]:checked,#quantity').each(function() {
tab[$(this).attr('name')] = parseInt($(this).val());
});
console.log(tab);
return tab;
}
function validate(s) {
//This is how we check that at least a checkbox is checked
/*if($("input:checkbox:not(:checked)").length == $('input[type=checkbox]').length){
$('#totalcost,#checkedcount').val(0);
} else {*/
$('#checkedcount').val(s);
$('#totalcost').val((parseInt($('#quantity').val()) * s));
$('#totalcount').val($('#quantity').val());
//}
}
$('*[data-in="num"],#quantity').on('change', function() {
var sum = 0;
$('[data-in="num"]:checked').each(function() {
sum += parseInt($(this).val());
});
validate(sum);
myArray = storeArray();
//myArray Object containing all input values
//console.log(myArray);
//This is how get the quantity for example
//console.log(myArray['quantity']);
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form>
<div id="CheckBoxList">
<label><input type="checkbox" id='game0' value="1" name="Apple" data-d="b" data-in="num">Apple</label>
<label><input type="checkbox" id='game1' value="2" name="Orange" data-d="b" data-in="num">Orange</label>
<label><input type="checkbox" id='game2' value="3" name="Pineaple" data-d="b" data-in="num">Pineaple</label>
<label><input type="checkbox" id='game3' value="4" name="Lemon" data-d="b" data-in="num">Lemon</label>
<label><input type="checkbox" id='game4' value="5" name="Mango" data-d="b" data-in="num">Mango</label>
</div>
<div id="RadioButtonList">
<label><input type="radio" id='pad' value="6" data-d="b" name="HI" data-in="num">Small Cup</label>
<label><input type="radio" id='pad1' value="7" data-d="b" name="HI" data-in="num">Medium Cup</label>
<label><input type="radio" id='pad2' value="8" data-d="b" name="HI" data-in="num">Big Cup</label>
</div>
<div id="SelectOptions">
<select name="quantity" id="quantity" data-d="b">
<option value="0">Select quantity</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
</select>
</div>
<code id="demo"></code>
total cost<input type="text" id="totalcost" value="">
<br>total Checked<input type="text" id="checkedcount" value="">
<br>total boxes<input type="text" id="totalcount" value="">
<!-- partial -->
</form>

Try with this code:
function storeArray() {
var tab = [];
$('*[data-in="num"]:checked,#quantity').each(function(index) {
tab[index] = {
name: $(this).attr('name'),
value: parseInt($(this).val())
});
return tab;
}

How to be simpler in this JavaScript?

I am trying to make a Js to search & filter items in JSON
so I use many radio in the "form" , the result will be [X,X,X,X,X,X]
I will set 50tags x 3(choose), I can feel my function will be large.
What ways can I change my function to be simpler?
function myFunction() {
var elements1 = document.getElementsByName("chair"),
elements2 = document.getElementsByName("car"),
elements3 = document.getElementsByName("house"),
elements4 = document.getElementsByName("tree"),
elements5 = document.getElementsByName("flower"),
elements6 = document.getElementsByName("grass");
var i;
for (var a = "", i = elements1.length; i--;) {
if (elements1[i].checked) {
var a = elements1[i].value;
break;
}
};
for (var b = "", i = elements2.length; i--;) {
if (elements2[i].checked) {
var b = elements2[i].value;
break;
}
};
for (var c = "", i = elements3.length; i--;) {
if (elements3[i].checked) {
var c = elements3[i].value;
break;
}
};
for (var d = "", i = elements4.length; i--;) {
if (elements4[i].checked) {
var d = elements4[i].value;
break;
}
};
for (var e = "", i = elements5.length; i--;) {
if (elements5[i].checked) {
var e = elements5[i].value;
break;
}
};
for (var f = "", i = elements6.length; i--;) {
if (elements6[i].checked) {
var f = elements6[i].value;
break;
}
};
var o2 = document.getElementById("output2");
o2.value = "[" + a + "," + b + "," + c + "," + d + "," + e + "," + f + "]";
o2.innerHTML = o2.value;
}
<form><input type="radio" id="chair1" name="chair" class="chair" value="1">
<input type="radio" id="chair0" name="chair" class="chair" value="0" checked>
<input type="radio" id="chair-1" name="chair" class="chair" value="-1">
<input type="radio" id="car1" name="car" class="car" value="1">
<input type="radio" id="car0" name="car" class="car" value="0" checked>
<input type="radio" id="car-1" name="car" class="car" value="-1">
<input type="radio" id="house1" name="house" class="house" value="1">
<input type="radio" id="house0" name="house" class="house" value="0" checked>
<input type="radio" id="house-1" name="house" class="house" value="-1">
<input type="radio" id="tree1" name="tree" class="tree" value="1">
<input type="radio" id="tree0" name="tree" class="tree" value="0" checked>
<input type="radio" id="tree-1" name="tree" class="tree" value="-1">
<input type="radio" id="flower1" name="flower" class="flower" value="1">
<input type="radio" id="flower0" name="flower" class="flower" value="0" checked>
<input type="radio" id="flower-1" name="flower" class="flower" value="-1">
<input type="radio" id="grass1" name="grass" class="grass" value="1">
<input type="radio" id="grass0" name="grass" class="grass" value="0" checked>
<input type="radio" id="grass-1" name="grass" class="grass" value="-1">
<div> <input type="button" value="Search" id="filter" onclick="myFunction()" /> </div>
</form>
<div id="output2"></div>

Give the form an id, and you can refer to it as an object.
function myFunction() {
var form = document.getElementById("myForm");
var parts = [
form.chair.value,
form.car.value,
form.house.value,
form.tree.value,
form.flower.value,
form.grass.value
];
var o2 = document.getElementById("output2");
o2.innerHTML = '[' + parts.join(',') + ']';
}
And this is an even simpler solution using a FormData object. It supports an arbitrary number of named form fields without having to actually name them in the function:
function myFunction() {
var myForm = document.getElementById('myForm');
var formData = new FormData(myForm);
var parts = Array.from(formData.values());
var o2 = document.getElementById("output2");
o2.innerHTML = '[' + parts.join(',') + ']';
}

Use document.querySelector() to directly select the value of the checked radio button based on element names.
function myFunction() {
var chair = document.querySelector('input[name="chair"]:checked').value;
var car = document.querySelector('input[name="car"]:checked').value;
var house = document.querySelector('input[name="house"]:checked').value;
var tree = document.querySelector('input[name="tree"]:checked').value;
var flower = document.querySelector('input[name="flower"]:checked').value;
var grass = document.querySelector('input[name="grass"]:checked').value;
var o2 = document.getElementById("output2");
o2.value = "[" + chair + "," + car + "," + house + "," + tree + "," + flower + "," + grass + "]";
o2.innerHTML = o2.value;
}

Use arrays!
function myFunction() {
var elem_ids = [ "chair", "car", "house", "tree", "flower", "grass"];
var elems = elem_ids.map(id => document.getElementById(id));
var elems_check_values = elems.map(el => {
// el is kind of an array so
for(var i = 0; i < el.length; ++i)
if(el[i].checked)
return el[i].value;
return undefined;
}).filter(value => value == undefined) // to filter undefined values;
var output = "[" + elems_check_values.join(",") + "]";
var o2 = document.getElementById("output2");
o2.innerHTML = output
}

Your issue can be generalized to: how can I aggregate values for all fields in a given form?
The solution is a function that can be merely as long as 5 lines, and work for any amount of inputs with any type. The DOM model for <form> elements provides named keys (eg, myform.inputName) which each have a value property. For radio buttons, eg myform.tree.value will automatically provide the value of the selected radio button.
With this knowledge, you can create a function with a simple signature that takes a form HTMLElement, and an array of field names for the values that you need, like below: (hit the search button for results, and feel free to change the radio buttons).
function getFormValues(form, fields) {
var result = [];
for (var i = 0; i < fields.length; i++) {
result.push(form[fields[i]].value);
}
return result;
}
document.getElementById('filter').addEventListener('click', function(e) {
var o2 = document.getElementById("output2");
o2.innerHTML = getFormValues(document.forms[0], ['chair','car','house','tree','flower','grass']);
});
<form><input type="radio" id="chair1" name="chair" class="chair" value="1">
<input type="radio" id="chair0" name="chair" class="chair" value="0" checked>
<input type="radio" id="chair-1" name="chair" class="chair" value="-1">
<input type="radio" id="car1" name="car" class="car" value="1">
<input type="radio" id="car0" name="car" class="car" value="0" checked>
<input type="radio" id="car-1" name="car" class="car" value="-1">
<input type="radio" id="house1" name="house" class="house" value="1">
<input type="radio" id="house0" name="house" class="house" value="0" checked>
<input type="radio" id="house-1" name="house" class="house" value="-1">
<input type="radio" id="tree1" name="tree" class="tree" value="1">
<input type="radio" id="tree0" name="tree" class="tree" value="0" checked>
<input type="radio" id="tree-1" name="tree" class="tree" value="-1">
<input type="radio" id="flower1" name="flower" class="flower" value="1">
<input type="radio" id="flower0" name="flower" class="flower" value="0" checked>
<input type="radio" id="flower-1" name="flower" class="flower" value="-1">
<input type="radio" id="grass1" name="grass" class="grass" value="1">
<input type="radio" id="grass0" name="grass" class="grass" value="0" checked>
<input type="radio" id="grass-1" name="grass" class="grass" value="-1">
<div> <input type="button" value="Search" id="filter"/> </div>
</form>
<div id="output2"></div>

The thing you need to do is break the code up into reusable chunks. So make a method to get the value. That will reduce a lot of code. After than, you should look at a way to reduce how many elements you need to list. Finally, find an easy way to fetch all the values.
So below is code that does this. It uses a helper method to get the elements, find the value. Than it uses an array to know what element groups to look for. And finally it uses map to iterate over the list so you do not have to code multiple function calls.
function getSelected (radioBtnGroup) {
// get the elements for the radio button group
var elms = document.getElementsByName(radioBtnGroup)
// loop over them
for(var i=0; i<elms.length; i++) {
// if checked, return value and exit loop
if (elms[i].checked) {
return elms[i].value
}
}
// if nothing is selected, return undefined
return undefined
}
// list the groups you want to get the values for
var groups = ['rb1', 'rb2', 'rb3', 'rb4']
// call when you want to get the values
function getValues () {
// use map to get the values of the rabio button groups.
// map passes the index value as the first argument.
// code is map(function(k){return getSelected(k)})
var results = groups.map(getSelected)
//displat the results
console.log(results);
}
document.querySelector('#btn').addEventListener('click', getValues);
<form>
<fieldset>
<legend>Item 1</legend>
<label><input type="radio" name="rb1" value="1-1"> One</label>
<label><input type="radio" name="rb1" value="1-2"> Two</label>
<label><input type="radio" name="rb1" value="1-3"> Three</label>
</fieldset>
<fieldset>
<legend>Item 2</legend>
<label><input type="radio" name="rb2" value="2-1"> One</label>
<label><input type="radio" name="rb2" value="2-2"> Two</label>
<label><input type="radio" name="rb2" value="2-3"> Three</label>
</fieldset>
<fieldset>
<legend>Item 3</legend>
<label><input type="radio" name="rb3" value="3-1"> One</label>
<label><input type="radio" name="rb3" value="3-2"> Two</label>
<label><input type="radio" name="rb3" value="3-3"> Three</label>
</fieldset>
<fieldset>
<legend>Item 4</legend>
<label><input type="radio" name="rb4" value="4-1"> One</label>
<label><input type="radio" name="rb4" value="4-2"> Two</label>
<label><input type="radio" name="rb4" value="4-3"> Three</label>
</fieldset>
<button type="button" id="btn">Get Results</button>
</form>
Personally I would not store the values in an array, I would use an object with key value pairs.
var results = groups.reduce(function (obj, name) {
obj[name] = getSelected(name)
return obj
}, {});

Add -remove an option to dropdown menu

I am trying to write to a function. Whn I check a checkbox, the items belongs to that checkbox item comes to dropdown menu, and when I uncheck it, it goes away from the dropdpwn. I can add, but cannot remove when I uncheck the checkbox.Here is my code.
var items = [
"#1001#item1#10.5#10#1#direc1#",
"#1002#item2#20.5#10#2#direc2#",
"#1003#item3#20.5#10#3#director3#",
];
function checkboxChange(ev) {
var count = items.length;
var select = document.getElementById('formsec');
for (var i = 0; i < count; i++){
if (ev.value=="1001" &&ev.checked ) {
var item = items[i];
var currentitem = item.split('#');
if (currentitem[5]=="1" ) {
var opt = document.createElement('option');
opt.value = currentitem[1];
opt.innerHTML = currentitem[2];
select.appendChild(opt);
}
HTML
<td>
Choose the item: </br>
<input type="checkbox" id="category1" name="choice" value="1001" onchange="checkboxChange(this)" />Category1<br />
<input type="checkbox" id="category2" name="choice" value="1002" onchange="checkboxChange(this)" />Category2<br />
<input type="checkbox" id="category3" name="choice" value="1003" onchange="checkboxChange(this)" />Category3<br />
</td>

Working example using querySelector and select.remove().
Only works with Category 1 because OP conditions:
if (ev.value == "1001")
if (currentitem[5] == "1")
var items = [
"#1001#item1#10.5#10#1#direc1#",
"#1002#item2#20.5#10#2#direc2#",
"#1003#item3#20.5#10#3#director3#",
];
function checkboxChange(ev) {
var count = items.length;
var select = document.getElementById('formsec');
for (var i = 0; i < count; i++) {
if (ev.value == "1001") {
var item = items[i];
var currentitem = item.split('#');
if (currentitem[5] == "1") {
if (ev.checked) {
var opt = document.createElement('option');
opt.value = currentitem[1];
opt.innerHTML = currentitem[2];
select.appendChild(opt);
} else {
var opt = document.querySelector("option[value='" + currentitem[1] + "']");
select.remove(opt);
}
}
}
}
}
<select id="formsec"></select>
<td>
Choose the item: <br />
<input type="checkbox" id="category1" name="choice" value="1001" onchange="checkboxChange(this)" /><label for="category1">Category1</label><br />
<input type="checkbox" id="category2" name="choice" value="1002" onchange="checkboxChange(this)" /><label for="category2">Category2</label><br />
<input type="checkbox" id="category3" name="choice" value="1003" onchange="checkboxChange(this)" /><label for="category3">Category3</label><br />
</td>

This may help you. I implement this without an array. Use an associated label with each checkbox.
function checkboxChange(ev) {
$('#formsec').html("");
$('input[type=checkbox]').each(function () {
var chk = (this.checked ? $(this).val() : "");
if(chk){
$('#formsec').append('<option value="'+chk+'" selected="selected">'+$("label[for='"+this.id+"']").text()+'</option>');
}
});
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
Choose the item:<br />
<input type="checkbox" id="category1" name="choice" value="1001" onchange="checkboxChange(this)" />
<label for="category1">Category1</label>
<br />
<input type="checkbox" id="category2" name="choice" value="1002" onchange="checkboxChange(this)" />
<label for="category2">Category2</label>
<br />
<input type="checkbox" id="category3" name="choice" value="1003" onchange="checkboxChange(this)" />
<label for="category3">Category3</label>
</div>
<select id="formsec"></select>

Instead setting an onChange handler in html I would recommend binding an input-handler and rebuild the selectbox each time, even on document load like
var items = [
"#1001#item1#10.5#10#1#direc1#",
"#1002#item2#20.5#10#2#direc2#",
"#1003#item3#20.5#10#3#director3#"
];
function rebuild() {
var select = document.getElementById('formsec');
select.innerHTML = "";
[].forEach.call(document.querySelectorAll("input[type=checkbox]"), (el) => {
if (el.checked) {
var opt = document.createElement('option');
var currentitem = items.find(
(item) => item.startsWith("#" + el.value)
).split("#");
opt.value = currentitem[1];
opt.innerHTML = currentitem[2];
select.appendChild(opt);
}
});
}
[].forEach.call(document.querySelectorAll("input[type=checkbox]"), (el) => {
el.addEventListener("input", rebuild);
});
rebuild();
Choose the item:<br>
<input type="checkbox" id="category1" name="choice" value="1001">Category1<br>
<input type="checkbox" id="category2" name="choice" value="1002" checked>Category2<br>
<input type="checkbox" id="category3" name="choice" value="1003">Category3<br>
<select id="formsec"></select>

How Do I count the selected checkbox in AngularJS?

/**
* #Summary: checkAllConnectedUser function, to create album
* #param: index, productObj
* #return: callback(response)
* #Description:
*/
$scope.shardBuyerKeyIdArray = [];
$scope.countBuyer = 0;
$scope.checkAllSharedBuyer = function(isChecked) {
if (isChecked) {
if ($scope.selectAll) {
$scope.selectAll = false;
} else {
$scope.selectAll = true;
}
angular.forEach($scope.selectedSharedBuyerObjectList, function(selectedBuyer) {
selectedBuyer.select = $scope.selectAll;
//IF ID WILL BE EXIST IN THE ARRAY NOT PSUH THE KEYID
if ($scope.shardBuyerKeyIdArray.indexOf(selectedBuyer.userTypeDto.keyId) == -1) {
$scope.shardBuyerKeyIdArray.push(selectedBuyer.userTypeDto.keyId);
$scope.countBuyer++;
}
});
} else {
$scope.selectAll = false;
//USED FOR UNCHECK ALL THE DATA ONE- BY-ONE
angular.forEach($scope.selectedSharedBuyerObjectList, function(selectedBuyer) {
selectedBuyer.select = $scope.selectAll;
var index = $scope.shardBuyerKeyIdArray.indexOf(selectedBuyer.userTypeDto.keyId);
$scope.shardBuyerKeyIdArray.splice(index, 1);
$scope.countBuyer--;
});
}
}
<div class="checkbox w3-margin" ng-if="selectedSharedBuyerObjectList.length > 0">
<span class="w3-right" ng-if="countBuyer">
<h5>You are selecting {{countBuyer}} buyers!</h5>
</span>
<label>
<input type="checkbox" ng-model="selectAll" ng-click="checkAllSharedBuyer(selectAll)"/>Check All
</label>
</div>
<div id="sharedRow" class="checkbox" ng-repeat="selectedBuyer in cmnBuyer = (selectedSharedBuyerObjectList | filter : userSearchInProduct
| filter : filterUser)">
<label>
<input type="checkbox" ng-model="selectedBuyer.select"
ng-change="selectedSharedBuyer($index, selectedBuyer.select, selectedBuyer.userTypeDto.keyId)"/>
{{selectedBuyer.personName}}
</label>
</div>
I have two list in which i have to count the select all checkbox length as well as single checkbox count my problem if the user un-check the ALL checkbox Checkbox count will be return -- what's the problem in my code?

$(function(){
var count = 0;
$('#sharedRow ').find('input[type=checkbox]').on('change',function(){
$('#msg').text('You are selecting '+$('#sharedRow ').find('input[type=checkbox]:checked').length+' buyers!')
})
$('#chkAll').on('change', function () {
if ($(this).is(':checked')) {
$('#sharedRow ').find('input[type=checkbox]').prop('checked', true);
$('#msg').text('You are selecting '+$('#sharedRow ').find('input[type=checkbox]:checked').length+' buyers!')
}
else {
$('#sharedRow ').find('input[type=checkbox]').prop('checked', false);
$('#msg').text('You are selecting '+$('#sharedRow ').find('input[type=checkbox]:checked').length+' buyers!')
}
});
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="checkbox w3-margin">
<span class="w3-right">
<h5 id="msg" >You are selecting 0 buyers!</h5>
</span>
<label>
<input id="chkAll" type="checkbox" />Check All
</label>
</div>
<div id="sharedRow" class="checkbox">
<label>
<input type="checkbox" value="1 Buyers" />1 Buyers
</label>
<label>
<input type="checkbox" value="2 Buyers" />2 Buyers
</label>
<label>
<input type="checkbox" value="3 Buyers" />3 Buyers
</label>
<label>
<input type="checkbox" value="4 Buyers" />4 Buyers
</label>
<label>
<input type="checkbox" value="5 Buyers" />5 Buyers
</label>
<label>
<input type="checkbox" value="6 Buyers" />6 Buyers
</label>
<label>
<input type="checkbox" value="7 Buyers" />7 Buyers
</label>
<label>
<input type="checkbox" value="8 Buyers" />8 Buyers
</label>
</div>
try this one. is it ok? if not then tell me what's wrong.

if you have a group of checkbox then you can find all selected checkbox.
$('div').find('input[type=checkbox]:checked').length;

If you only need the number
var count = $scope.selectedSharedBuyerObjectList.reduce(function(sum, item) {
return (item.select) ? sum + 1 : sum;
}, 0);
If you need the filtered array
var selected = $scope.selectedSharedBuyerObjectList.filter(function(item) {
return item.select;
});
var count = selected.length;
Or do it using plain old loop
var count = 0;
for (i = 0; i < $scope.selectedSharedBuyerObjectList.length; i++) {
if ($scope.selectedSharedBuyerObjectList.select) count++;
}

check all boxes checked when click on parent checkbox only with Javascript? [duplicate]

I have an HTML page with multiple checkboxes.
I need one more checkbox by the name "select all". When I select this checkbox all checkboxes in the HTML page must be selected. How can I do this?

<script language="JavaScript">
function toggle(source) {
checkboxes = document.getElementsByName('foo');
for(var checkbox in checkboxes)
checkbox.checked = source.checked;
}
</script>
<input type="checkbox" onClick="toggle(this)" /> Toggle All<br/>
<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo" value="bar4"> Bar 4<br/>
UPDATE:
The for each...in construct doesn't seem to work, at least in this case, in Safari 5 or Chrome 5. This code should work in all browsers:
function toggle(source) {
checkboxes = document.getElementsByName('foo');
for(var i=0, n=checkboxes.length;i<n;i++) {
checkboxes[i].checked = source.checked;
}
}

Using jQuery:
// Listen for click on toggle checkbox
$('#select-all').click(function(event) {
if(this.checked) {
// Iterate each checkbox
$(':checkbox').each(function() {
this.checked = true;
});
} else {
$(':checkbox').each(function() {
this.checked = false;
});
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="checkbox" name="checkbox-1" id="checkbox-1" />
<input type="checkbox" name="checkbox-2" id="checkbox-2" />
<input type="checkbox" name="checkbox-3" id="checkbox-3" />
<!-- select all boxes -->
<input type="checkbox" name="select-all" id="select-all" />

I'm not sure anyone hasn't answered in this way (using jQuery):
$( '#container .toggle-button' ).click( function () {
$( '#container input[type="checkbox"]' ).prop('checked', this.checked)
})
It's clean, has no loops or if/else clauses and works as a charm.

I'm surprised no one mentioned document.querySelectorAll(). Pure JavaScript solution, works in IE9+.
function toggle(source) {
var checkboxes = document.querySelectorAll('input[type="checkbox"]');
for (var i = 0; i < checkboxes.length; i++) {
if (checkboxes[i] != source)
checkboxes[i].checked = source.checked;
}
}
<input type="checkbox" onclick="toggle(this);" />Check all?<br />
<input type="checkbox" />Bar 1<br />
<input type="checkbox" />Bar 2<br />
<input type="checkbox" />Bar 3<br />
<input type="checkbox" />Bar 4<br />

here's a different way less code
$(function () {
$('#select-all').click(function (event) {
var selected = this.checked;
// Iterate each checkbox
$(':checkbox').each(function () { this.checked = selected; });
});
});

Demo http://jsfiddle.net/H37cb/
<script type="text/javascript" src="http://code.jquery.com/jquery-latest.min.js" /></script>
<script type="text/javascript">
$(document).ready(function(){
$('input[name="all"],input[name="title"]').bind('click', function(){
var status = $(this).is(':checked');
$('input[type="checkbox"]', $(this).parent('li')).attr('checked', status);
});
});
</script>
<div id="wrapper">
<li style="margin-top: 20px">
<input type="checkbox" name="all" id="all" /> <label for='all'>All</label>
<ul>
<li><input type="checkbox" name="title" id="title_1" /> <label for="title_1"><strong>Title 01</strong></label>
<ul>
<li><input type="checkbox" name="selected[]" id="box_1" value="1" /> <label for="box_1">Sub Title 01</label></li>
<li><input type="checkbox" name="selected[]" id="box_2" value="2" /> <label for="box_2">Sub Title 02</label></li>
<li><input type="checkbox" name="selected[]" id="box_3" value="3" /> <label for="box_3">Sub Title 03</label></li>
<li><input type="checkbox" name="selected[]" id="box_4" value="4" /> <label for="box_4">Sub Title 04</label></li>
</ul>
</li>
</ul>
<ul>
<li><input type="checkbox" name="title" id="title_2" /> <label for="title_2"><strong>Title 02</strong></label>
<ul>
<li><input type="checkbox" name="selected[]" id="box_5" value="5" /> <label for="box_5">Sub Title 05</label></li>
<li><input type="checkbox" name="selected[]" id="box_6" value="6" /> <label for="box_6">Sub Title 06</label></li>
<li><input type="checkbox" name="selected[]" id="box_7" value="7" /> <label for="box_7">Sub Title 07</label></li>
</ul>
</li>
</ul>
</li>
</div>

When you call document.getElementsByName("name"), you will get a Object. Use .item(index) to traverse all items of a Object
HTML:
<input type="checkbox" onclick="for(c in document.getElementsByName('rfile')) document.getElementsByName('rfile').item(c).checked = this.checked">
<input type=​"checkbox" name=​"rfile" value=​"/​cgi-bin/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​includes/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​misc/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​modules/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​profiles/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​scripts/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​sites/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​stats/​">​
<input type=​"checkbox" name=​"rfile" value=​"/​themes/​">​

Slightly changed version which checks and unchecks respectfully
$('#select-all').click(function(event) {
var $that = $(this);
$(':checkbox').each(function() {
this.checked = $that.is(':checked');
});
});

My simple solution allows to selectively select/deselect all checkboxes in a given portion of the form, while using different names for each checkbox, so that they can be easily recognized after the form is POSTed.
Javascript:
function setAllCheckboxes(divId, sourceCheckbox) {
divElement = document.getElementById(divId);
inputElements = divElement.getElementsByTagName('input');
for (i = 0; i < inputElements.length; i++) {
if (inputElements[i].type != 'checkbox')
continue;
inputElements[i].checked = sourceCheckbox.checked;
}
}
HTML example:
<p><input onClick="setAllCheckboxes('actors', this);" type="checkbox" />All of them</p>
<div id="actors">
<p><input type="checkbox" name="kevin" />Spacey, Kevin</p>
<p><input type="checkbox" name="colin" />Firth, Colin</p>
<p><input type="checkbox" name="scarlett" />Johansson, Scarlett</p>
</div>
I hope you like it!

<html>
<head>
<script type="text/javascript">
function do_this(){
var checkboxes = document.getElementsByName('approve[]');
var button = document.getElementById('toggle');
if(button.value == 'select'){
for (var i in checkboxes){
checkboxes[i].checked = 'FALSE';
}
button.value = 'deselect'
}else{
for (var i in checkboxes){
checkboxes[i].checked = '';
}
button.value = 'select';
}
}
</script>
</head>
<body>
<input type="checkbox" name="approve[]" value="1" />
<input type="checkbox" name="approve[]" value="2" />
<input type="checkbox" name="approve[]" value="3" />
<input type="button" id="toggle" value="select" onClick="do_this()" />
</body>
</html>

Try this simple JQuery:
$('#select-all').click(function(event) {
if (this.checked) {
$(':checkbox').prop('checked', true);
} else {
$(':checkbox').prop('checked', false);
}
});

JavaScript is your best bet. The link below gives an example using buttons to de/select all. You could try to adapt it to use a check box, just use you 'select all' check box' onClick attribute.
Javascript Function to Check or Uncheck all Checkboxes
This page has a simpler example
http://www.htmlcodetutorial.com/forms/_INPUT_onClick.html

This sample works with native JavaScript where the checkbox variable name varies, i.e. not all "foo."
<!DOCTYPE html>
<html>
<body>
<p>Toggling checkboxes</p>
<script>
function getcheckboxes() {
var node_list = document.getElementsByTagName('input');
var checkboxes = [];
for (var i = 0; i < node_list.length; i++)
{
var node = node_list[i];
if (node.getAttribute('type') == 'checkbox')
{
checkboxes.push(node);
}
}
return checkboxes;
}
function toggle(source) {
checkboxes = getcheckboxes();
for (var i = 0 n = checkboxes.length; i < n; i++)
{
checkboxes[i].checked = source.checked;
}
}
</script>
<input type="checkbox" name="foo1" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo2" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo3" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo4" value="bar4"> Bar 4<br/>
<input type="checkbox" onClick="toggle(this)" /> Toggle All<br/>
</body>
</html>

It's rather simple:
const selectAllCheckboxes = () => {
const checkboxes = document.querySelectorAll('input[type=checkbox]');
checkboxes.forEach((cb) => { cb.checked = true; });
}

If adopting the top answer for jQuery, remember that the object passed to the click function is an EventHandler, not the original checkbox object. Therefore code should be modified as follows.
HTML
<input type="checkbox" name="selectThemAll"/> Toggle All<br/>
<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo" value="bar4"> Bar 4<br/>
Javascript
$(function() {
jQuery("[name=selectThemAll]").click(function(source) {
checkboxes = jQuery("[name=foo]");
for(var i in checkboxes){
checkboxes[i].checked = source.target.checked;
}
});
})

<asp:CheckBox ID="CheckBox1" runat="server" Text="Select All" onclick="checkAll(this);" />
<br />
<asp:CheckBoxList ID="CheckBoxList1" runat="server">
<asp:ListItem Value="Item 1">Item 1</asp:ListItem>
<asp:ListItem Value="Item 2">Item 2</asp:ListItem>
<asp:ListItem Value="Item 3">Item 3</asp:ListItem>
<asp:ListItem Value="Item 4">Item 4</asp:ListItem>
<asp:ListItem Value="Item 5">Item 5</asp:ListItem>
<asp:ListItem Value="Item 6">Item 6</asp:ListItem>
</asp:CheckBoxList>
<script type="text/javascript">
function checkAll(obj1) {
var checkboxCollection = document.getElementById('<%=CheckBoxList1.ClientID %>').getElementsByTagName('input');
for (var i = 0; i < checkboxCollection.length; i++) {
if (checkboxCollection[i].type.toString().toLowerCase() == "checkbox") {
checkboxCollection[i].checked = obj1.checked;
}
}
}
</script>

that should do the job done:
$(':checkbox').each(function() {
this.checked = true;
});

You may have different sets of checkboxes on the same form. Here is a solution that selects/unselects checkboxes by class name, using vanilla javascript function document.getElementsByClassName
The Select All button
<input type='checkbox' id='select_all_invoices' onclick="selectAll()"> Select All
Some of the checkboxes to select
<input type='checkbox' class='check_invoice' id='check_123' name='check_123' value='321' />
<input type='checkbox' class='check_invoice' id='check_456' name='check_456' value='852' />
The javascript
function selectAll() {
var blnChecked = document.getElementById("select_all_invoices").checked;
var check_invoices = document.getElementsByClassName("check_invoice");
var intLength = check_invoices.length;
for(var i = 0; i < intLength; i++) {
var check_invoice = check_invoices[i];
check_invoice.checked = blnChecked;
}
}

This is what this will do, for instance if you have 5 checkboxes, and you click check all,it check all, now if you uncheck all the checkbox probably by clicking each 5 checkboxs, by the time you uncheck the last checkbox, the select all checkbox also gets unchecked
$("#select-all").change(function(){
$(".allcheckbox").prop("checked", $(this).prop("checked"))
})
$(".allcheckbox").change(function(){
if($(this).prop("checked") == false){
$("#select-all").prop("checked", false)
}
if($(".allcheckbox:checked").length == $(".allcheckbox").length){
$("#select-all").prop("checked", true)
}
})

As I cannot comment, here as answer:
I would write Can Berk Güder's solution in a more general way,
so you may reuse the function for other checkboxes
<script language="JavaScript">
function toggleCheckboxes(source, cbName) {
checkboxes = document.getElementsByName(cbName);
for (var i = 0, n = checkboxes.length; i < n; i++) {
checkboxes[i].checked = source.checked;
}
}
</script>
<input type="checkbox" onClick="toggleCheckboxes(this,\'foo\')" /> Toggle All<br/>
<input type="checkbox" name="foo" value="bar1"> Bar 1<br/>
<input type="checkbox" name="foo" value="bar2"> Bar 2<br/>
<input type="checkbox" name="foo" value="bar3"> Bar 3<br/>
<input type="checkbox" name="foo" value="bar4"> Bar 4<br/>
<input type="checkbox" name="foo" value="bar5"> Bar 5<br/>

$(document).ready(function() {
$(document).on(' change', 'input[name="check_all"]', function() {
$('.cb').prop("checked", this.checked);
});
});

Using jQuery and knockout:
With this binding main checkbox stays in sync with underliying checkboxes, it will be unchecked unless all checkboxes checked.
ko.bindingHandlers.allChecked = {
init: function (element, valueAccessor) {
var selector = valueAccessor();
function getChecked () {
element.checked = $(selector).toArray().every(function (checkbox) {
return checkbox.checked;
});
}
function setChecked (value) {
$(selector).toArray().forEach(function (checkbox) {
if (checkbox.checked !== value) {
checkbox.click();
}
});
}
ko.utils.registerEventHandler(element, 'click', function (event) {
setChecked(event.target.checked);
});
$(window.document).on('change', selector, getChecked);
ko.utils.domNodeDisposal.addDisposeCallback(element, () => {
$(window.document).off('change', selector, getChecked);
});
getChecked();
}
};
in html:
<input id="check-all-values" type="checkbox" data-bind="allChecked: '.checkValue'"/>
<input id="check-1" type="checkbox" class="checkValue"/>
<input id="check-2" type="checkbox" class="checkValue"/>

to make it in short-hand version by using jQuery
The select all checkbox
<input type="checkbox" id="chkSelectAll">
The children checkbox
<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">
<input type="checkbox" class="chkDel">
jQuery
$("#chkSelectAll").on('click', function(){
this.checked ? $(".chkDel").prop("checked",true) : $(".chkDel").prop("checked",false);
})

Below methods are very Easy to understand and you can implement existing forms in minutes
With Jquery,
$(document).ready(function() {
$('#check-all').click(function(){
$("input:checkbox").attr('checked', true);
});
$('#uncheck-all').click(function(){
$("input:checkbox").attr('checked', false);
});
});
in HTML form put below buttons
<a id="check-all" href="javascript:void(0);">check all</a>
<a id="uncheck-all" href="javascript:void(0);">uncheck all</a>
With just using javascript,
<script type="text/javascript">
function checkAll(formname, checktoggle)
{
var checkboxes = new Array();
checkboxes = document[formname].getElementsByTagName('input');
for (var i=0; i<checkboxes.length; i++) {
if (checkboxes[i].type == 'checkbox') {
checkboxes[i].checked = checktoggle;
}
}
}
</script>
in HTML form put below buttons
<button onclick="javascript:checkAll('form3', true);" href="javascript:void();">check all</button>
<button onclick="javascript:checkAll('form3', false);" href="javascript:void();">uncheck all</button>

Here is a backbone.js implementation:
events: {
"click #toggleChecked" : "toggleChecked"
},
toggleChecked: function(event) {
var checkboxes = document.getElementsByName('options');
for(var i=0; i<checkboxes.length; i++) {
checkboxes[i].checked = event.currentTarget.checked;
}
},

html
<input class='all' type='checkbox'> All
<input class='item' type='checkbox' value='1'> 1
<input class='item' type='checkbox' value='2'> 2
<input class='item' type='checkbox' value='3'> 3
javascript
$(':checkbox.all').change(function(){
$(':checkbox.item').prop('checked', this.checked);
});

1: Add the onchange event Handler
<th><INPUT type="checkbox" onchange="checkAll(this)" name="chk[]" /> </th>
2: Modify the code to handle checked/unchecked
function checkAll(ele) {
var checkboxes = document.getElementsByTagName('input');
if (ele.checked) {
for (var i = 0; i < checkboxes.length; i++) {
if (checkboxes[i].type == 'checkbox') {
checkboxes[i].checked = true;
}
}
} else {
for (var i = 0; i < checkboxes.length; i++) {
console.log(i)
if (checkboxes[i].type == 'checkbox') {
checkboxes[i].checked = false;
}
}
}
}

You can Use This code.
var checkbox = document.getElementById("dlCheckAll4Delete");
checkbox.addEventListener("click", function (event) {
let checkboxes = document.querySelectorAll(".dlMultiDelete");
checkboxes.forEach(function (ele) {
ele.checked = !!checkbox.checked;
});
});

You can use this simple code
$('.checkall').click(function(){
var checked = $(this).prop('checked');
$('.checkme').prop('checked', checked);
});

Maybe a bit late, but when dealing with a check all checkbox, I believe you should also handle the scenario for when you have the check all checkbox checked, and then unchecking one of the checkboxes below.
In that case it should automatically uncheck the check all checkbox.
Also when manually checking all the checkboxes, you should end up with the check all checkbox being automatically checked.
You need two event handlers, one for the check all box, and one for when clicking any of the single boxes below.
// HANDLES THE INDIVIDUAL CHECKBOX CLICKS
function client_onclick() {
var selectAllChecked = $("#chk-clients-all").prop("checked");
// IF CHECK ALL IS CHECKED, AND YOU'RE UNCHECKING AN INDIVIDUAL BOX, JUST UNCHECK THE CHECK ALL CHECKBOX.
if (selectAllChecked && $(this).prop("checked") == false) {
$("#chk-clients-all").prop("checked", false);
} else { // OTHERWISE WE NEED TO LOOP THROUGH INDIVIDUAL CHECKBOXES AND SEE IF THEY ARE ALL CHECKED, THEN CHECK THE SELECT ALL CHECKBOX ACCORDINGLY.
var allChecked = true;
$(".client").each(function () {
allChecked = $(this).prop("checked");
if (!allChecked) {
return false;
}
});
$("#chk-clients-all").prop("checked", allChecked);
}
}
// HANDLES THE TOP CHECK ALL CHECKBOX
function client_all_onclick() {
$(".client").prop("checked", $(this).prop("checked"));
}